1. Field of the Invention
The present invention relates generally to a ballast for energizing fluorescent lamps, and more particularly to an improved electronic ballast for use in energizing fluorescent lamps.
2. Description of the Prior Art
Ballasts for energizing fluorescent lamps are commercially of the type that employ a transformer having primary and secondary windings wound around a common magnetic core. Although simple in construction, the conventional ballast which operates at 60 or 120 Hz may be audibly noisy and generates voltage spikes on the leading edge of each positive and negative alternation. This disadvantageously results in the production of relatively large quantitites of electrical noise. Another disadvantage is that the ballast is heavy and because of core losses is not as energy efficient as desired, and may be subject to heating problems.
Furthermore, it should be noted that the fluorescent tubes energized by the ballast have been connected in a parallel circuit. This consequently requires relatively large quantities of current to turn the lamps on and is plagued by the presence of circulating currents which results in additional power loss and inefficiency.